I have a 94z A4 with hotcam, 1.6 rr, headers, cai, ewp, dyno tune, and a brand new msd opti. And my car will not start!!!! Ive been through several opti's in the past two months and im tired of it.

Ive replaced coil, opti, starter, plugs, wires, checked ignition module, and went through all grounds.

after my first couple of opti replaces car would fire right up, it might only run for four days but it would fire right up. Now with the new msd opti it will only start once every 25 attempts. And thats whats driving me crazy. The fact that it will start every 25 times; idles fine, revs fine, no breaking up, just perfect. But as soon as you turn it off its over.

When i say that it want start, it turns over, and fires but it want crank. and when you switch the key off it blows back through intake and little bit of gas fumes come out. i know it has fire because i hooked a spark plug checker up to it and it lit up.

When i say blow back i dont mean back fire, I think its just the compression in the engine.

I thought it was a gas problem like fuel not getting into cylinders, but i sprayed ether into it and it did not crank.

Could it possibly be the computer? please help.

 

I would check computer, at least for any codes it may have thrown. Could point you in a direction at least.

 

Did you adjust the timing inside the MSD opti. It has adjustments in it that might be off.

 

Timing has been adjusted on msd opti, thats fine, the computer however has not been tested. Im putting a new one in monday. so maybe it will work then.

 

Check your ignition switch.

 

I second the ignition switch. Easy to test BEFORE you go pulling it apart. Got meter?

 

Put brand new computer in still does the same thing. It just drives me crazy that it will crank every 24 hrs. Not 12hrs not 15hrs but every 24 or more hours it will crank????

Im going to check the ignition switch tonight.

 

I just read shoebox's homepage about the ignition switch and it said that the tale-tale signs of an ignition switch failure was that the cluster guages would not work. Mine work fine. And the fuel pump works fine.

So do yall have any other ideas.

PS I know the fuel pump works fine because i have a nitrous line hooked up to the schrader valve with a fuel pressure switch and you can bleed the lines down and as soon as you turn key on pressure comes back up to 42ish lbs.

 

I went thru the hassle of a cranking but no start condition like what you seem to have. I tried to follow all the schematics in my factory shop manual as well as several sites including Shoebox's. Somehow my methods got lost in translation because after spending for a new GM opti, coil, and module, new Bosch O2s and new NGK plugs, the damn thing still wouldn't start and the car was down for like 6 months since I only had time for it on the weekends.

So I finally broke down and sent it to a reputable shop, they diagnosed and replaced the weatherpack connector to the coil and she started right up! A $40.00 part, $80.00 in diagnosis and labor and I was driving down the road. Plus all the loot I spent for the parts I had already spent which was probably not necessary in the first place, but the car was due for a tune up anyways. Good luck.

 

well i guess its time to break out the ohm meter and check the weather packs.

 

ITS FIXED. It was the damn MSD coil. I just got it like 2 months ago from pepboys. Well i appriciate all the help.